Metals such as lead, and most metal halides such as copper bromide, can operate as visible lasers at temperatures below the .about. 1100.degree. C. limit of quartz envelopes. This feature is especially attractive for practical laser systems, since quartz optical windows, quartz:molybdenum seals and relatively straightforward glassblowing fabrication techniques can be employed for the laser discharge tube assemblies. The quartz laser discharge tube technology can operate with very long lifetimes in the all-hot, sealed-off configuration.
An additional requirement for metal or metal halide lasers is a low inductance electrical circuit to provide very rapid current rise times for the laser discharge, and a thermal enclosure to employ waste heat from the discharge in raising the tube temperature to the desired operating range. This combination of features provides efficient electrical excitation at high temperatures without the need for an external heating source. In addition, all tube materials must be capable of withstanding high temperatures, thermal cycling and exposure to metal halides. The tube design described herein satisfies all of these requirements simultaneously.